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光学学报 2003年第S1期23卷 827-828页

作者： Fan Guo-fang ,Yang Ji-sheng,Sang Wei, Xu Ke-xinDepartment of Applied Physics, state key {2. of precision technology and instruments, tianjin university.P.R.China, Tel:86-2.-2.402.84,Fax:86-2.-2.890681 ,E-mail:fgf78@*** Department of Applied Physics Tianjin UniversityP.R.China state key {2. of precision technology and instruments Tianjin UniversityP.R.China

In this paper we calculated the acoustic intensity distribution of different transducers, and designed acousto-optic tunable filter(AOTF) based on different transducers. Through the experiment, we find sidelobe can be... 详细信息

关键词： AOTF on be for of in

APPLICATION OF CDF(2.2. TO ANALYSIS OF SUSPENDED SEDIMENT IMAGE

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Particuology 2005年第4期3卷 204-207页

作者： Hequan Sun,Liansheng Yu,Yongming Shen,Daoyin Yu and Guangwen Zhu College of precision Instrument and Opto-electronics Engineering, tianjin university, {2. 300072. P. R. China state key laboratory of Coastal and Offshore Engineering, Dalian university of technology, Dalian 11602., P. R, China National Ocean technology Center, {2. 300111, P. R. China College of precision Instrument and Opto-electronics Engineering Tianjin University Tianjin 300072 P. R. China National Ocean technology Center Tianjin 300111 P. R. China Author to whom correspondence should be addressed. state key {2. of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 P. R. China

The characteristics of suspended sediment image can be reflected by the coefficients of biorthogonal wavelet transform of CDF(2.2.. Based on the power distribution in different scales, an adaptive algorithm is proposed in this paper, whereby the coefficients are adjusted non-linearly. The particle information can be well retained while the useless background is removed. In this way, satisfactory binary image can be obtained for further analysis of the sediment particle.

关键词： suspended sediment image particle biorthogonal wavelet CDF(2 2.

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高精度电容测微仪关键技术

天津大学学报（自然科学与工程技术版） 2004年第9期37卷 787-791页

作者：李建文刘书亮付敬业周涛郑义忠天津大学内燃机燃烧学国家重点实验室天津300072 中国人民解放军军事交通学院天津300161 天津大学精密仪器与光电子工程学院天津300072

针对非接触式电容测微技术的应用问题,介绍了非接触式高精度电容测微仪的基本工作原理及关键技术,给出了仪器的主要结构,对仪器电路进行了模块化设计,研究分析了实际测量过程中不可避免的各种误差,并提出了相应的消除或修正方法.研究结... 详细信息

针对非接触式电容测微技术的应用问题,介绍了非接触式高精度电容测微仪的基本工作原理及关键技术,给出了仪器的主要结构,对仪器电路进行了模块化设计,研究分析了实际测量过程中不可避免的各种误差,并提出了相应的消除或修正方法.研究结果表明,探头的有效直径为1mm时,仪器的分辨率可达1nm,测量范围为±5μm.探头的有效直径为9mm时,分辨率可降到0.1μm,测量范围可扩大到±1mm,动态频响0～4kHz.

关键词：电容测微仪非接触测量误差修正

小波变换在体表子宫电信号降噪处理方面的应用

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天津大学学报（自然科学与工程技术版） 2002年第4期35卷 491-496页

作者：谌雅琴李刚姜苇叶文宇虞启琏天津大学精密测试技术及仪器国家重点实验室天津300072

主要讨论了小波变换在体表子宫电信号降噪处理方面的应用 ,提出了一种基于多孔分解、采用非对称滤波器的降噪算法 .与经典降噪技术相比 ,该方法不仅简单 ,能够快速实现。

关键词：降噪处理仪表子宫电信号小波变换降噪算法信号处理子宫肌肉活动

A PHENOMENON OF LT-GaAs PHOTOCONDUCTIVE SWITCH TRIGGERED BY 800nm FEMTOSECOND LASER

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A PHENOMENON OF LT-GaAs PHOTOCONDUCTIVE SWITCH TRIGGERED BY ...

Performance Optimization of Dispersion-Managed WDM Systems Based on Four-Wave Mixing

2.06年中国机械工程学会年会暨中国工程院机械与运载工程学部首届年会

作者： QI Sen, LIU Qinggang, HE Botao, CHEN Qing, ZHANG Chaoyan, HU Xiaotang state key Lab of {2. measuring technology & Instrument, tianjin university, tianjin China 300072

The Ti oxide is used as insulator between the electrodes to substitute the air gap of photoconductive semiconductive switch (PCSS). The width of the oxide is smaller than 100nm, the electrodes and sub

关键词： Photoconductive Semiconductor Switch (PCSS) femtosecond Laser non-linearity working mode.

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光学学报 2003年第S1期23卷 39-40页

作者： Shiming Gao Changxi Yang Guofan Jinstate key {2. of precision Measurement technology and instruments, Tsinghua university, Beijing 100084, P. R. China, state key {2. of precision Measurement technology and instruments Tsinghua University Beijing 100084 P. R. China

We systemically investigate the interchannel four-wave mixing (FWM) in dispersion-managed WDM systems with arbitrary launch position. We optimize the number of fiber sections, and the dispersion ratio for the system p... 详细信息

关键词： WDM as FWM Performance Optimization of Dispersion-Managed WDM Systems Based on Four-Wave Mixing of Four Wave on

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三维数字像重建及显示的软件系统实现

天津大学学报（自然科学与工程技术版） 2001年第4期34卷 420-424页

作者：史伟强张宗华彭翔胡小唐天津大学精密测试技术及仪器国家重点实验室天津300072

提出了一种三维数字像重建及其显示的软件系统结构设计和实现方法 .整个软件系统结构是根据面向对象的程序设计思想 ,利用 Visual C+ + 6 .0的编程环境和 MFC提供的各种资源建立的 .三维数字成像系统的功能模块 ,如三维编码数据的采集... 详细信息

提出了一种三维数字像重建及其显示的软件系统结构设计和实现方法 .整个软件系统结构是根据面向对象的程序设计思想 ,利用 Visual C+ + 6 .0的编程环境和 MFC提供的各种资源建立的 .三维数字成像系统的功能模块 ,如三维编码数据的采集、解调、重建和三维数字像的显示 ,都通过相应的应用类设计实现 .此外 ,通过将 Open GL技术嵌入到软件系统实现了三维数字图像的各种快速显示方法 ,包括顶点显示、网格显示和纹理映射显示 .结果证明 ,该软件系统提供了友好的图形用户界面、高效的数据处理和重建。

关键词：三维数字成像相位映射空间表面重软件系统

Orthogonal linear polarized lasers (II)——Study on the physical phenomena

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Progress in Natural Science:Materials International 2005年第10期 3-14页

作者： ZHANG Shulian and LIU Gang (The state key {2. of precision Measurement technology and instruments, Department of precision instruments, Tsinghua university, Beijing 100084, China)

The physical phenomena and corresponding theoretical analysis of orthogonal polarized laser are reviewed. Four lasers (or systems) with orthogonal polarized beams arc involved. For the birefringence dual frequency laser, its physical phenomena discussed include the alternation between strong mode competition and medium mode competition in cavity tuning; the range of frequency difference of strong mode competition (about 0-40 MHz); four polarization statuses (o-light oscillating but e-light extinguishing, both o-light and elight oscillating, e-light oscillating but o-light extinguishing, both o-light and e-light extinguishing) in cavity tuning; the tuning curves of frequency difference; the influence of optical activity of quartz crystal on polarization direction; and the aberrance of frequency splitting. For the Birefringence-Zeeman dual frequency laser, we focus on its intensity tuning and frequency difference tuning. For the feedback system of orthogonally polarized laser, we discuss the mutual suppression between two orthogonal frequencies, intensity exchange between two orthogonal frequencies and double of intensity fringe frequency. For orthogonally polarized LD-pumped Nd:YAG microchip laser, its property of the dependence of intensity sensitivity on frequency difference is described.

关键词： orthogonally polarized laser frequency splitting cavity tuning mode competition intra-cavity birefringence Zee-man effect frequency difference optical activity optical feedback.

Research on Electric Impedance Spectroscopy of Living Cell Suspensions by a Chip with Microelectrodes

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稀有金属材料与工程 2006年第S3期 429-432页

作者： Xing Yang~(1,2.3) Zhaoying Zhou~(1,2.3) Mingfei Xiao~(1,2.3) Ying Wu~(1,2.3) Shangfeng Liu~4 (1.MEMS Lab.,Department of precision instruments & Mechanology,Tsinghua {2.,Beijing 100084,China) (2.Micro-Nano technology Research Center,Tsinghua {2.,Beijing 100084,China) (3.state key laboratory of precision Measurement technology and instruments,Tsinghua {2.,Beijing 100084,China) (4.School of Medicine,Tsinghua {2.,Beijing 100084,China)

A microfabricated electrical impedance spectroscopy (EIS) chip with microelectrodes was *** substrate and the electrodes of the chip were made of glass and gold,*** experimental results demonstrated that the EIS-chip could distinguish different solutions (physiological saline,culture medium,living cell suspension etc.) by scanning from 10Hz to 45kHz.A 6-element circuit model was used for fitting the real part and the imaginary part admittance curves of the living cell *** actual circuit was also built and tested to verify the 6-element circuit model *** micro-EIS chip has several advantages including the use of small sample volumes,high resolution and ease of *** shows good application prospects in the areas of cellular electrophysioiogy,drug screening and bio-sensors etc.

关键词： electrical impedance spectroscopy(EIS) microelectrode living cell suspension 6-element